1. Field of the Invention
The instant invention relates to a safety device useful in fighting fires in open tanks and other vertical structures wherein a fire fighter has to be able to traverse the upper extremity of the structure in order to fight the fire. This device is especially useful in fighting fires in oil tanks having floating roofs.
2. Backgroung of the Prior Art
Movable suspension devices adapted for use in securing and supporting workmen in an elevated position adjacent a vertical building wall are well known in the art. Such devices may be constructed to enable the workman to move selectively, horizontally and vertically, to a desired position along the wall. Generally such devices are supported on the parapet or upper wall ledge of the building or other vertical structure, such as a bridge, tower, fence, etc. A device of this sort is disclosed in U.S. Pat. No. 3,620,331. This device would not be useful for fighting fires in an open tank since the workman is held suspended at a point below the portion of the device which engages the upper ledge or parapet of the building. In such position, the workman would not be able to peer over the upper edge of the tank and direct water or other fire-suffocating agent into the interior of the open tank. Furthermore, in this device the workman is seated on a suspended support platform. It is clear that during movement of the platform the worker is secured only by his ability to maintain his grasp on the cables attached to the supporting platform. In particular, there is no method for securing the workman to the device other than the workman's own physical grasp.
Fire escapes which are affixed to the upper portion of the building to enable occupants of the building to flee to the ground in the event of a fire are also well known.
In U.S. Pat. No. 434,709, a ladder is secured to a rope which traverses the outer walls of a typical building. Again, this device would not be useful in conjunction with an open tank since there is no independent means for securing a fire fighter, who would have to be able to manipulate a hose or other devices to smother the fire. Furthermore, the device would not enable the fire fighter to extend himself above the top of a tank since the device terminates at the point at which it is secured to the ledge. Finally, this reference is inapplicable to fighting fires in tanks, in that the purpose of the device is to enable a person to exit from some point in the building to the ground as opposed to enabling a person to maintain himself at the upper circumference of the tank for the purpose of peering into and fighting a fire contained therein.
Therefore, it is one object of this invention to provide a device to enable a fire fighter to traverse the upper circumference of an open tank in a position to enable him to peer into and fight a fire by directing a fire smothering agent into the tank.
It is another object of this invention to provide a safety device which the fire fighter can propel about the circumference of a tank by his own physical effort while fighting a fire therein.
It is another object of this invention to provide a device which is easily and quickly secured to the top of an open tank for the purpose of securing a fire fighter thereto.
Other objects and advantages of the instant invention will be apparent from a careful reading of the specification below.